Siggraph 2014: Day 3

AUG 12 2014, TUESDAY

TUESDAY 0945..1045

  • amd
  • mantle
    • new low level programming interface for windows pc
    • designed in collaboration with top game developers
    • lightweight driver that allows direct access to GPU
    • good for big game: battlefield 4
  • mantle benefits
    • higher graphics performance
    • empowering lower spec system
    • predictable performance behaviour
    • sharing optimizations between PCs and game consoles
    • new rendering techniques
      • more flexible, can be used on other gpu like intel and nvidia
  • why a new api?
    • success of the GCN architcture
      • uniform d
    • many collaboration with gaming industry and AMD
    • not a replacement for industry-standard API like DirectX or OpenGL
  • the small batch problem
    • draw calls are generated by the CPU to create work for the GPU
    • too many draw calls can make a system CPU-limited, leaving GPU under-utilized
    • batchig many objects into a single draw call adds code complexity and constrains artists
      • 3-5K draw calls
      • 10K draw calls
      • draw calls possible with heavy optimizations
      • 100K+ -> draw call target with mantle, 60fps
  • multi-threading
    • BEFORE
      • multi-threading gmae engines using directx and opengl
      • cpu0 -> game
      • cpu1 -> render
      • cpu2 -> dirver render
      • doesn’t scale beyond 2-3 cores
      • latency limits performance
      • driver thread often boecomes a bottleneck
    • AFTER
      • with mantle
      • cpu0 -> game
      • cpu1 -> render
      • cpu2 -> render
      • .. cpu5 -> render
      • scale linearly with number of cores
      • minimal latency
      • no driver thread overhead
  • MANTLE core features
    • app-controlled execution model
    • generalized resources
    • monolithic pipelines
    • fiexlible memory management
    • page talbe remapping
    • hybrid resource binding model
    • bindless -> huge in next
  • MANDTLE extended features
    • advanced flow control
    • advanced anti-aliasing functions
    • multi-device support
    • asynchronous compute
  • prog graphics application potential to use mantle
    • graphics api overhead
      • large/complex cad & DCC models consist of many individual assemblies, not easy or in many cases
      • AEC models of complex
      • Mantle reduces API overhead, avoiding inefficient state changes between those
    • multi-threading
      • CAD
    • memory management
      • cloud/vdi solutions may require more efficient use of graphics memory, partitioning, allocation,etc
      • mantle can provide
    • fast syncronization between compute eigne and graphic engines
    • drive optimizations
      • avoid driver bottlenects
      • dumb driver
    • data transfer control over PCIE
    • optimzations
      • optimize shader code to gain performance
      • use highly optimized code for specific
    • vertical market segments where mantle can help
      • cad, medical
    • to get the evaulation copy of firepro mantle driver
      • [email protected]
      • firepro developer sdk
      • http://developer.amd.com/tools-and-sdks/graphics-development/firepro-sdk
    • intel is approaching to them
  • ACTION ITEM
    • needs a slide
    • it’s a replacement of opengl or directx
    • will it be good? not sure

TUESDAY 1100..1200

  • maya
    • what’s new in maya 2015 ext 1
    • could import with dropbox a 123?
    • openubdiv surface
    • alembic
    • biforost -> prt
    • xgen
    • rendering
      • vp2.0
      • color management
      • maya hardware can be saved as exr
  • retopology options
    • auto and guided retopology – mudbox
    • cloud integration: reality capture data <- maya 2015 ext 1
    • gpu caching
    • data exchanging
    • maya quad draw -> manual retopology
  • MAYA 2015 new modeling toolkit
    • Mesh Editing Tools:
      • Target Weld
  • new boolean
    • will give you cut and uv will be there too
    • gemoetry + texture
  • new reduce tool
    • looks good, poly reduction
    • make nice clean geometry
    • some triangles, ngons quad -> click quad draw tool in modeling tools
      • hit magnet tool
      • and use quad draw
  • how to clean the dense scan model data

    • file -> send to unity, send to unreal
    • file -> game exporter
    • fbx review tool: free download
    • file -> cloud import/export => a360, 123D, dropbox
    • pipleline cache -> gpu ahe export -> exported to alembic

    • grab mesh

    • use magnet tool
    • quad draw tool
    • dragging and draw the quads
    • remeshing the surface
    • relax tool
    • soft seletion
    • sticking to the original surface
    • transfer map option
    • look at uv first
  • new uv editor
    • plannar mapping
    • grab edge of the head
    • cut and open up the head
    • fenecing
    • unfold3dunfold
    • unfold3d optimize
  • supports ptex file
  • ACTION ITEM
    • get the slide
    • trynew modeling tool
    • ptex
    • try export to alembic

TUESDAY 1230..0130

  • OSL open shading language from sony image works
  • more renderers and apps
  • released OSL 1.5
    • reparameter (enables lookdev tools)
    • shadergroup – specific attributes
      • per-group renderer output
      • re
  • featured change: group pickling
    • http://opensource.imageworks.com/?p=osl
  • send the param as a string
  • serilized a shader group
  • archive a shaer group, inluding .oso file
    • debugging
    • benchmarking/ optimization target
    • can be run with testshader or other tools – no renderer needed!
  • on deck
    • make it faster for SIMD-oriented renderers:
    • output cuda kernels somehow
    • optimized new usage cases
    • ecosystem

pixar

  • new version of renderman
  • renderman RIS & OSL wayne wooten
  • native ray trace renderer
  • whats’ RIS?:
    • integrators,
    • VCM bi-directional path tracer
    • BXDFs
      • glass, skin, disney
    • patterns
      • osl, SeExpr, Texture, Voronoise
  • SSS
  • Why RIS?
  • visual effects, 2014
    • simplfy workflow
    • fast feedback
    • easy to use
    • heavy gemoetry
    • volumes & particles
    • raytrace everything
  • typical day at work
    • check last night’s renders
    • dailies
    • breaks
    • meetings/ coffee
    • make it pretty(4h)
    • launch nightly build
    • 4-6 hours to get things done of your time
  • OSL
  • *** image from a wooden clock from carbon frame
    • oak feeding Disney BXDF
      • from Michel J. Anders
    • carbon fiber feeding Blend BXDF
      • from v0ray examples
    • backdrop 1 line simpletex.osl
    • OSL api is easy to use
  • OSL UDIM Texture
    • used in Mari
      • stands for U-dimension
      • UDIM(u,v) = 1000 + (10*u) + v + 1
  • OSL UDIM Texture
    • written in c++
  • OSL UDIM Texture
    • original naive implementation was very slow
      • vtune to the rescue
      • threading took a hit( multi-thread usting)
      • string manipulation was shlow
    • what to do?
      • bottleneck was OSL codebase
      • discussed with Larry Gritz
      • just under a week it ran fast
  • OSL UDIM Texture
    • open source really works
  • Evaluation Results
    • OSL pros
      • feels ‘homey’ to RSL users
      • targeted language and features
      • avoids plugin versionitis
    • OSL cons
      • disngle point, lack of SIMD/coherence
      • JIT time
      • LLVM targets libm.so,

OSL Gaffer

  • John Haddon, imageengine
  • What’s gaffer?
    • applicationf framework for VFX
    • node based
    • open source (BSD)
      • cortex,
  • two birds
    • gaffer -> lots of node, to manipulate scene hirerace
    • none for deforming each objs
    • need to allow
    • play with OSL
      • no renderer suppported it
  • loading shaders
    • search for shaders on env[“OSL_SHADER_PATHS”]
      • build menu
  • node graph
  • executing shaders
    • conver node network to OSL::shadingAttribState
    • implement renderservices::get_attributes() to provide access to prim vars and image channels
    • call shading system::execute() with fake shaderglobals
    • convert colsurecolor result ack to prim vars and image channels
    • abuse debug() closure
  • noise
  • show some demo
  • further work
    • UI implenetation
    • optimisation
    • using osl as a shading language
    • image convolution/ edge access
    • nei
  • http://github.com/imageengine/gaffer

#

  • general heckenberg? animal logic
  • physically based renderman pipeline => with renderman
  • very successful in 4-5 studios
  • “lego movie”
  • plastic -> lighting directions, specular lights
  • retraining the renderer translator
  • shader translation

TUESDAY 0200..0300

  • BOF, alembic
  • no major releases
  • moved to github/alembic/alembic
  • a little more collaboration
  • focus on stability, optimization
  • a few improvement, namespace support,
  • slow dev now.
  • will add hooks on importer and exporter
  • doulbe precision issue
  • game use abc becuase it contains more info than fbx
  • ACTION ITEM
    • check out github repo

TUESDAY 0300..0400

  • vray: sig: vray day1: Digital Domain Rendering Heavy Assets: X-Men’s RFK Stadium
  • merged light cache
  • only 1 gi compuattion for the whole sequence
  • tree
    • 400 individual trees
    • billons of polygons
    • 42 species,
    • speed tree -> speedbridge => sent to DD pipeline
    • lookdev done in maya and 7vray
    • vray proxy -> full gemoetry -> vrayproxy
      • super fast scene handling
      • fast export and renders

Tehe RFK Stadium

  • lidar scan to sue as modeling reference
  • stadium size adjusted to fit over the whilehouse and match the live action
  • 40k vs 60k seats
  • main strcutre: concnreat
  • small details: lights, air con boxes, pipies and seats
  • split into 7 sections
  • shading and textures applied to what’s in camera only
    • keep the geo -> for gi calc
    • blew shading and texture
  • textures are from
  • lookdev done in maya & vray

destroying everything, stadium

  • stadium lifted by its metallic structure
  • use of our deferred render pipieline to render the seat
  • create a vrscene for a single seat -> one vrscene contains geo, mtl, tex
  • massive open file format
    • CDL rigging description
    • APF aniamtion info
  • render
    • load vrscene ->
  • landed stadium
    • destoyed stadium modelling from FX drop simulation
    • new faces created for the inside parts of the cube
    • no uvs on the new faces
    • first step ->
      • rgb mask color set in the vrayproxy accessed via vrayvertexcolor node
    • world space noise not “sticking” to the geometry
    • adding ‘rest’ attribute as another color set
    • noise mapped on the inside faces using rest color set as coordinate space
  • deep images
    • smoke coming out from houdini
    • all renders done with vray
    • breaking up was all done in houdini
  • vgo
    • tree -> proxy, geo proxy
  • render at 2K or 3K
    • using the external render time
    • amazon ec2?
    • rendering everything in house
    • render with vrimage and convert to exr
  • ACTION ITEM
    • should apply on the farm
    • one gi computation
    • vrayproxy
    • CDL, APF, vrscene

TUESDAY 0345..0445

  • Gaffer: vfx
  • kartick will go, i won’t

TUESDAY 0400..0500

  • renderfarming
  • file size -> use isilon
  • cloud -> use managed service and set up the bandwidth
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